Re: [PATCH v9 14/14] drm/mediatek: Add interface to allocate Mediatek GEM buffer.

Daniel Vetter
2016-01-12T22:40:10Z

On Tue, Jan 12, 2016 at 11:02 PM, Rob Herring <robh+dt@kernel.org> wrote:
> On Tue, Jan 12, 2016 at 9:15 AM, Philipp Zabel <p.zabel@pengutronix.de> wrote:
>> From: CK Hu <ck.hu@mediatek.com>
>>
>> Add an interface to allocate Mediatek GEM buffers, allow the IOCTLs
>> to be used by render nodes.
>> This patch also sets the RENDER driver feature.
>
> But it should not a be render node unless it has a GPU AFAIK. Then
> again, I still don't understand the madness of every driver defining
> their own buffer ioctls either. The only line remotely h/w specific
> here is mtk_drm_gem_create call.

Support gem_create/mmap_offet alone is indeed pointless without some
real support for gpu workloads. For plain display drivers the dumb
buffer api, plus prime/dma-buf import should be plenty enough.

The usual reason for doing this is some blob driver for opengl that
can't be open-source, which is a big no-go for upstream.

Imo best to just rip this out, consider it nacked without full-blown
userspace and whatever else is needing these buffers.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch